The family decided to stand guard at night on Monday at the cow shed which also served as a hen coop, after 48 chickens went missing in a month.

"Instead of the dogs, we watched in horror as the calf, whom we had fondly named Lal, sneak to the coop and grab the little ones with the precision of a jungle cat," Gour Ghosh, his brother, said.

Local television pictures showed the cow grabbing and eating a chicken in seconds and a vet confirmed the case.

"We think lack of vital minerals in the body is causing this behavior. We have taken a look and have asked doctors to look into the case immediately," Mihir Satpathy, a district veterinary officer, said by phone.